1. Field of the Invention
This invention relates generally to devices for cleaning conveyor belts that are used to transport particulate matter such as coal, sand, gravel, crushed rock, etc. More particularly this invention relates to novel wiping blades which are designed to wipe clean, as nearly as possible, conveyor belts upon which there has built up a layer or coating of waste material such as rock, sand, etc., called cake during transfer of unprocessed coal. This invention is to be distinguished from the prior art as a novel blade or blade element as opposed to art-known conveyor belt cleaning devices.
2. Description of the Prior Art
The build up of waste materials on conveyor belts designed for particulate hauling has been a long standing problem. In the field of coal transportation to which this invention has particular applicability there accumulates over a period of time a layer of waste material consisting of a find powder of rock, sand and other waste material normally associated with the moving of coal and other raw material. This layer of waste material, sometimes referred to as cake, can build up and interfere with the operation of the conveyor by clogging moving parts. As a solution to the build up of waste material generally on a conveyor belt a number of conveyor belt cleaning devices have been designed and patented. One of the simplest devices consists of a series of blades aligned parallel to each other and transversely across the conveyor belt as shown in West German Patent No. 1,108,137. Other devices, utilizing a single continuous unitary blade concept are described in U.S. Pat. Nos. 3,722,667, 3,267,970, 3,841,470, 3,782,534 and 2,514,780. Other devices utilizing a plurality blade approach may be found in U.S. Pat. Nos. 3,504,786, 3,055,229 and 1,733,456. It is to be noted that in each of these prior art devices the wiper element usually consists of a single, continuous, generally rectangularly shaped blade, or, more simply, a straight edge.
None of the prior art devices have satisfactorily solved the problem of cleaning material such as cake from a conveyor belt. After the straight edge type blade had passed over the belt, a great deal of the material still remained.